随着第五代移动通信(5th generation mobile communication,5G)基站建设数量的剧增,5G基站的备用电池将是一个具有巨大潜能的储能资源。我国电力市场化改革正不断推进,研究5G基站的备用储能参与电力市场交易是实现电网和通信运营商互利...随着第五代移动通信(5th generation mobile communication,5G)基站建设数量的剧增,5G基站的备用电池将是一个具有巨大潜能的储能资源。我国电力市场化改革正不断推进,研究5G基站的备用储能参与电力市场交易是实现电网和通信运营商互利共赢的有效途径。考虑到5G基站备用储能参与电力市场的特殊性,建立了计及退化成本和可调度容量的基站储能电池模型,并将零散的基站聚合成5G基站虚拟电厂(virtual power plant,VPP)。然后,将5G基站VPP作为独立的竞价主体,构建双层的电能量-调频辅助服务市场交易决策模型,并利用KKT(Karush-Kuhn-Tucker)条件和对偶理论将双层模型转化为可解的混合整数规划问题。最后,通过算例评估了5G基站备用储能的可调度容量以及所提交易决策模型的有效性。展开更多
Clustering or connected dominating set (CDS) both approaches can establish a virtual backbone (VB) in wireless sensor networks (WSNs) or wireless mesh networks (WMNs). Each cluster consisting of a cluster head (CH) an...Clustering or connected dominating set (CDS) both approaches can establish a virtual backbone (VB) in wireless sensor networks (WSNs) or wireless mesh networks (WMNs). Each cluster consisting of a cluster head (CH) and its neighboring nodes can form a dominating set. After some bridging nodes were selected, cluster heads (CHs) connected through these bridging nodes naturally formed a CDS. Although CDS provides obvious backbone architecture, however, the number of cluster heads and bridging nodes may be too large, this may cause the loss of advantages of virtual backbone. When we effectively reduce their numbers, more effectively WCDS (Weakly Connected Dominating Set) can be fining out. Some essential topics on constructing WCDS-based VB in WSN/WMN are discussed in this paper. From the point of view of three different protocol layers, including network (NWK) layer, MAC layer, and physical (PHY) layer, we explore their cross-layer research topics and design algorithms. For NWK layer, area-based WCDS algorithms and routing strategies including via VB and not via VB are discussed. For MAC layer, a WCDS-based energy-efficient MAC protocol is presented. For PHY layer, battery-aware alternative VB selections and sensor nodes with different transmission ranges are addressed.展开更多
In this paper, we present a magnetocardiogram （MCG） simulation study using the boundary element method （BEM） and based on the virtual heart model and the realistic human volume conductor model. The different contr...In this paper, we present a magnetocardiogram （MCG） simulation study using the boundary element method （BEM） and based on the virtual heart model and the realistic human volume conductor model. The different contributions of cardiac equivalent source models and volume conductor models to the MCG are deeply and comprehensively investigated. The single dipole source model, the multiple dipoles source model and the equivalent double layer （EDL） source model are analysed and compared with the cardiac equivalent source models. Meanwhile, the effect of the volume conductor model on the MCG combined with these cardiac equivalent sources is investigated. The simulation results demonstrate that the cardiac electrophysiological information will be partly missed when only the single dipole source is taken, while the EDL source is a good option for MCG simulation and the effect of the volume conductor is smallest for the EDL source. Therefore, the EDL source is suitable for the study of MCG forward and inverse problems, and more attention should be paid to it in future MCG studies.展开更多
文摘随着第五代移动通信(5th generation mobile communication,5G)基站建设数量的剧增,5G基站的备用电池将是一个具有巨大潜能的储能资源。我国电力市场化改革正不断推进,研究5G基站的备用储能参与电力市场交易是实现电网和通信运营商互利共赢的有效途径。考虑到5G基站备用储能参与电力市场的特殊性,建立了计及退化成本和可调度容量的基站储能电池模型,并将零散的基站聚合成5G基站虚拟电厂(virtual power plant,VPP)。然后,将5G基站VPP作为独立的竞价主体,构建双层的电能量-调频辅助服务市场交易决策模型,并利用KKT(Karush-Kuhn-Tucker)条件和对偶理论将双层模型转化为可解的混合整数规划问题。最后,通过算例评估了5G基站备用储能的可调度容量以及所提交易决策模型的有效性。
文摘Clustering or connected dominating set (CDS) both approaches can establish a virtual backbone (VB) in wireless sensor networks (WSNs) or wireless mesh networks (WMNs). Each cluster consisting of a cluster head (CH) and its neighboring nodes can form a dominating set. After some bridging nodes were selected, cluster heads (CHs) connected through these bridging nodes naturally formed a CDS. Although CDS provides obvious backbone architecture, however, the number of cluster heads and bridging nodes may be too large, this may cause the loss of advantages of virtual backbone. When we effectively reduce their numbers, more effectively WCDS (Weakly Connected Dominating Set) can be fining out. Some essential topics on constructing WCDS-based VB in WSN/WMN are discussed in this paper. From the point of view of three different protocol layers, including network (NWK) layer, MAC layer, and physical (PHY) layer, we explore their cross-layer research topics and design algorithms. For NWK layer, area-based WCDS algorithms and routing strategies including via VB and not via VB are discussed. For MAC layer, a WCDS-based energy-efficient MAC protocol is presented. For PHY layer, battery-aware alternative VB selections and sensor nodes with different transmission ranges are addressed.
基金supported by the State Key Development Program for Basic Research of China (Grant Nos. 2007CB512100 and2006CB601007)the National Natural Science Foundation of China (Grant No. 10674006)+2 种基金the National High Technology Research and Development Program of China (Grant No. 2007AA03Z238)China Postdoctoral Science Foundation (Grant No. 20090461376)the Fundamental Research Funds for the Central Universities (Grant No. KYJD09001)
文摘In this paper, we present a magnetocardiogram （MCG） simulation study using the boundary element method （BEM） and based on the virtual heart model and the realistic human volume conductor model. The different contributions of cardiac equivalent source models and volume conductor models to the MCG are deeply and comprehensively investigated. The single dipole source model, the multiple dipoles source model and the equivalent double layer （EDL） source model are analysed and compared with the cardiac equivalent source models. Meanwhile, the effect of the volume conductor model on the MCG combined with these cardiac equivalent sources is investigated. The simulation results demonstrate that the cardiac electrophysiological information will be partly missed when only the single dipole source is taken, while the EDL source is a good option for MCG simulation and the effect of the volume conductor is smallest for the EDL source. Therefore, the EDL source is suitable for the study of MCG forward and inverse problems, and more attention should be paid to it in future MCG studies.
